This invention generally relates to an apparatus and method for the inspection of newly formed, hot glass containers. More particularly, this invention relates to such an apparatus wherein the heat radiation of the newly formed glass containers is sensed for inspection purposes. Specifically, this invention relates to such an inspection device which will allow removal of malformed or misoriented glass containers from a single file stream of glass containers.
After formation in a bottle making machine, such as the well-known IS machine, glass containers are transported in single file on a conveyor to an annealing lehr. In order to be properly loaded into the lehr, the containers must be standing upright on their bases. In many cases, the glass containers pass through a tunnel in which a metal oxide coating is applied to their outer surfaces. This tunnel is positioned intermediate the forming machine and the lehr. Glass containers which are lying down on the conveyor or two glass containers which are stuck together can jam in the tunnel as well as cause difficulty during the transfer into the lehr. Glass containers with badly bent necks, so-called "leaners", are so obviously defective that they should be removed from the stream of containers as soon as possible.
The area adjacent the glass container forming machine presents a very hostile environment for inspection equipment. Despite the need for a device to detect and reject glass containers oriented or distorted as described above, to date I am not aware of any device which will serve this function reliably and inexpensively. In my invention, relatively rugged and simple lead sulfide cells sense heat radiation from glass containers shortly after they leave the forming machine. A logic unit, which may be fully protected from the hostile environment, then processes the electrical signals resulting from sensing of the heat radiation and determines whether to accept or reject every glass container that passes the sensing cells.
Some examples of prior art devices may be seen in the following U.S. Patent Nos. 3,248,845; 3,365,699; 3,506,840; 3,549,890; 3,529,169; 3,620,629; 3,621,266; 3,716,136; 3,731,205; and 3,754,123.